Filter



H. L. DICK May 25, 1937.

FILTER Original Filed June 10, 1952 2 Sheets-Sheet l Herber L DZCC- GMA/(Ri, +wmdm,

(Zag/5 H. L. DICK May 25, 1937.,

FILTER Original Filed June 10, 1952 2 Sheets-Sheet 2 Iridenr Herber L. Dck

By M ,UM -tt Patented Mary 25, 1937 UNITED STATES PATENT oFEiCE Application' June` 1o. 1932,= serial N5. 616,381

Renewed 'October 2l, 1936 6 Claims.

The present invention relates to iilters andhas vparticular reference to improvements in filters of -the type especially adapted for use in` purifying water for drinking purposes, andthe like.

The water of most municipal systemsv contains l "relatively large quantities of various impurities, such as organic matter, dirt, chemicals' such as chlorine, and even bacteria, which impart a disagreeable color, taste, and odor to the water,-

thereby rendering it V.undesirable for drinking purposes. f

.Various attempts havebeen made to provide a :Iilter which may beused ,tov purify water for household consumption. For example, stone fil- ]5 ters have-been employed rin this` connection forsometime. Stone `filters are objectionable for several reasons, including their relatively slow rate of ow,`necessity for frequent cleaning, and `failure to eiiminatecolor, taste and odor from the water. v

`A principal object of the present invention is to provide an improved method and apparatus for the purification of water or other liquids.

A further object is to provide a pressure iilter which will eiectively remove color, taste, and odor from water, as well as impurities such as suspended-solids and colloids.

A still further object is to provide an improved filtering element and method for making the same.

Another object is to provide a .filter of the household type in which the raw water is forced under pressure through a layer of a charge of prepared solids hydrostatically deposited upon a lter charge retainer such as cloth, paper or other retainers known in the art. v

Still another object is the provision of a filter having a large filtering surface which occupies a `relatively small space, so arranged as to require infrequent cleaning, and, when necessary, being easily cleaned and recharged.

These and other objects will be apparent from a consideration of the following description and r) by reference to the accompanying drawings, in

which Fig. 1 is a sectional view of a filter made in accordance with my invention;

Fig. v2 is a cross sectional view taken along line 2--2 of Fig. l;

Fig. 3 Ais a sectional View of a modified filter i made in accordance with my invention;

Fig. 4 is a plan view. partly in section, showing my improved filter element; Fig. 5 is an enlarged fragmentary view showing (ci. 21o-165) a section'of the ltering element shown in Fig. 4; and

Fig. 6 Vis an enlarged perspective view of the drainage seal washers used in connection with the filtering element. 5

It will be recognized that my improved iilter is of general application, but for purposes of illustration and explanation, it will be described with reference to the purification of water for household purposes. 10

In the drawings I represents a cylindrical casing or container which has a bottom section 2 of inverted conical shape. The central portion of the bottom section is iiattened at 3 and provided with an inlet opening. An inlet conduit d com- 15 i municates with the inlet opening and is secured to the portion 3 by means of a distributor head 5 which extends from the inside of the casing through the inlet opening and engages the conduit by means of suitable threads, a washer 20 being interposed between the bottom section and the conduit Il to insure a water-tight connection.

The distributor head 5 is provided with a plurality of openings 6 which are preferably tangential to the vertical opening 'l in order to 25 agitate or produce a swirling motion of the water as it enters the bottom of the container. This swirling motion of the incoming water acts to disperse the charge thoroughly throughout the container, whereby the charge forms a dense uniform 30 cake of iinely comminuted particles upon the filter charge retainer when filtration takes place. The swirling water also reagitates any` loose particles of the charge which fall from the filter charge retainer to the bottom of the container, 35 permitting them again to beI deposited on the retainer, as will be described more specifically here,- inafter.

The upper edge of the container l is turned outwardly and downwardly to form an attaching 40 rim 8. A top 9 is removably attached to the container by means of bolts I0 extending through theperipheral portion of the top and engaging an attaching ring I I which iits beneath the attaching rim 8. To provide a water-tight connection be- 5 tween the top and the container, a gasket I2 is seated in a channel in the under side of the top and presses against the rim 8.

An outlet conduit I3 is mounted in a suitable opening IB in the top or cover 9 by means of en- 50 gagement of the downwardly extending portion I5 with a threaded nut I6, a washer I1 rendering the connection water-tight. The upper portion of the outlet conduit communicates with a valved faucet I8 by which the flow of water through the 55 held under the pressure of the source of supply. If desired, a valve -may be included'in the inlet conduit in addition to or in. place Aof the valve in the outlet conduit, andv it will be noted that when lthe valve is placed in the inlet conduit the container is under atmospheric pressure when this valve is closed.

Asshown in Fig. 4, the filter element which is used in connection with my filter is produced by coverings. suitable rigid drainage member I 9 with a filter cloth or other suitable retaining member 20,'the free edges of which extend beyond the drainage membery and are sealed.

In accordance with aA preferred form of my l invention, the free'edges of the cloth are formed into an integral and water-tight union 2| by means of a water insoluble adhesive agent. It is preferred to treat the free edges of the cloth with unvulcanized rubber and to vulcanize the treated edges together. 'I'he resultant union is firm, permanent and entirely water-tight.

The wire screen which constitutes the drainage member I9 in the modifications shown in the drawings ls provided with an outlet opening intermediate its ends and preferably adjacent its central portion. On each side of the drainage member I9 and surrounding the outlet opening therein is mounted a drainage seal washer 22 which is secured to the screen or otherwise held in place. The drainage seal washers are provided with drainage channels 23 in order that the flltrate may pass into the outlet opening with minimum resistance.

The filter cloth extends over these drainage seal washers and is provided on each of its sides with an opening corresponding to the outlet opening in the wire screen. A headed drainage cap 24 abuts the filter cloth on one side of the drainage member I9 and has a hollow cylindrical portionY 25 extending through the outlet opening in the drainage member and protruding from the opposite side of the -filter element. Suitable perforations 26 are provided in the cylindrical portion 25 for drainage of the filtrate. An outlet connection 21engages the protruding portion of the drainage cap 24 and ls held in abutting relation to the filter cloth by means of threads 28.

By tightening the headed drainage cap 24 within the outlet connection 21, the filter cloth, which is preferably impregnated with rubber or similar substance about the openings, is held tightly between the drainage seal washer 22 and the outlet connection 21 on one side and between `the other drainage seal Washer 22 and the drainage cap 24 on the opposite side, thereby forming a water-tight joint.

The filter cloth preferably is secured about the wire' drainage member I9 while the latter is in substantially fiat form, as shown in Fig. 4. After formation of the sealed union 2| the rectangular wire screen and filter cloth are bent or formed into any suitable tortuous shape, the outside contour of which conforms substantially to the shape of the container. By forming the filter element in this manner a large surface or filter area is provided within a relatively small space. In the modifications shown in the drawings, the ends of the filter element are bent in the same direction about the central portion and then doubled back in the same direction so that the ends are adjacent the central portion. It will be understood that my object is to provide a tortuous shapedY filter element and that the particular shape imparted to the filter element is immatefilter is controlled.' It will be seen that the' inlet vconduit 4 maintains the container full of water portions of the tortuous filter element is desirably made such/that the layers of deposited charge on 'said adjacent portions will not toucliv or interfere with each other.

The outlet connection 21 communicates with and rigidly connected to the outlet conduit I3 by means of a suitable threaded pipe 29. By l this means the filter element isv removedfrom the container with removal of the top, thereby making the interior of the filter easily accessible for cleaning and/or replacement of parts.

In the modification shown in Fig. 3, the inlet conduit and outlet conduit are both mounted in the top of the filter, the container I having a continuous bottom wall. An inlet pipe 30 communicates with the inlet conduit 4 in this modiflcation and extends downwardly adjacent the bottom of the container, terminating in a nozzle 3I whichproduces a swirling or agitatlng motion in the water at the bottom vof the container.

Before theA filter is completely assembled, a

vquantity of finely divided or Vcommlnuted filter charge is preferably wetted or dampened and1 placed in the container. The nature and quantity of the charge will depend upon suchvfactors as the resultsdeslred, the length of time the filter is to be used before cleaning and recharging, the closeness oi' adjacent surfaces of the filtering element, and the characteristics of the water to be purified. Combinations of various filtering materials may be employed as the charge, or various materials may be used alone, as will be understood by one skilled in the art. In a modification which I have found particularly desirable in the purification of water for drinking purposes, finely divided particles of activated carbon are employed as the principal element of the charge, and with the activated carbon may be combined filter aids such as a diatomaceous earth. For example, 100 grams of nely comminuted activated carbon perl square foot of filtering area may be employed alone as the charge, or may be mixed with 15 grams of prepared diatomaceous earth or kieselguhr.

Where a carbonaceous charge is employed, I have found it highly desirable to Wet the charge prior to closing the filter, since the finely divided carbon would otherwise remain in the filter for some time before becoming wetted by the water passing through the filter.

In operation, the inlet conduit is mounted to a suitable pressure line, such as a city supply system, and water is introduced into the container under pressure. Due to the swirling and agitatlng motion produced in the water as it enters the container, the finely divided charge is agitated from the bottom of the container and dispersed in the water as it rises in the container. The differential pressure set up when the faucet I8 is opened causes the water to pass through the filter cloth 20 and to travel along the drainage member I9 to the outlet opening, from which the filtrate passes through the outlet connection 21 and into the outlet conduit. Passage of the water through the lter cloth causes the suspended particles of the charge to be hydrostatically deposited on the filter cloth, thereby forming a uniform layer 32 which covers the filter cloth. Thereafter, the Water must pass through the layer of the charge before passing through the filter cloth. Thus, the impurities of the water are retained on the charge rather than on the filter cloth. Although the particles aoansss of the, charge are unconiined, I have found that once theseparticles form a layer over thevillter cloth there is little tendency for the charge to drop oif and fall tothe bottom ofthe container.

V vIn case any of the charge does fall to the bottom The filter element may then be placed under a flowing stream of water whereby the lter charge and impurities are washed from the filter cloth. To recharge the apparatus, it ordinarily is necessary merely to'add a fresh lfilter charge to the container and replace the filter element and top,

replacement of the filterv cloth usually being unnecessary. The fresh charge is' desirablyA furnished to users of thev apparatus in a dampened condition and sealed in a suitable container.v

` In many municipal water systems the water is treated witha relatively large quantity of chlorine which remains in the water and imparts a disagreeable taste thereto. My illter is operable to remove the taste of chlorine from the water whena carbonaceous charge is employed, thereby rendering the water desirable for drinking purposes.

Due to the large filter area presented in my filter, the rate of flow is considerably higher than in prior filters occupying a similar space. 'Ihis filter area also provides a large surface for the 40 deposit of water impurities whereby their accumulation per unit area is suiciently slow to permit extended periods of operation before the rate of filtration decreases to an unsatisfactory point.

The filter cloth orother charge retainer em- 45 ployed is preferably suiiiciently porous to permit a free iiow and sufiiciently retentive to prevent passage therethrough of solid particles of the charge. By sealing the free edges of the filter cloth with a water insoluble adhesive agent, parti- "o cles of the charge and unfiltered water are prevented from passing between adjacent edges of the filter cloth without passing through the charge. r It is preferred to locate the outlet conduit for "5 the filter element adjacent the central portion thereof in order that the ltrate from each half of the filter element will have substantially the same distance to travel, thus distributing the differential pressure and resistance.

Many variations of my invention will occur to one skilled in the art and such modifications as come within the spirit of my invention are intended to be included in the appended claims.

1. A method of `forming a filter element which comprises providing a rigid drainage member, enclosing said member with ariilter cloth, and sealing adjacent free edges of said cloth together with a water insoluble adhesive to form an integral union.

2. A method of forming a filter element, which comprises covering a rigid drainage member with a filter cloth, sealing together adjacent free edges of said cloth with a water insoluble adhesive agent, and bending said drainage member and filter cloth into a desired tortuous shape.

3. A water filter element, comprising a rigid drainage member surrounded by a filter cloth,

the adjacent free edges of said cloth being sealed together with a water insoluble adhesive agent to form a water-tight union.

4. In a water-treating apparatus for the intermittent purification of water as for domestic use, a pressure container, means for introducing a swirling and agitating stream of water into the bottom of said container under pressure including a cap member in the lower portion of said container having a central conduit and a series of branch conduits extending outwardly therefrom in a direction substantially tangential to said central conduit, a top for the container, an outlet conduit suspended to said top, a filter element communicating with said outlet conduit, including a vertically positioned pervious drainage member provided with an opening intermediate its ends and top and bottom. a filter cloth surrounding said drainage member and having an opening corresponding to the opening in said drainage member, and an outlet connection connecting the opening in said drainage member with said outlet conduit to suspend said drainage member within the container, and a layer of a filter charge hydrostatically deposited on said filter cloth, said vertically Ypositioned filter element being bent into tortuous shape, and said container being free from obstructions between the bottom thereof and said filter element.

5. A method of forming a filter element which comprises providing a rigid drainage member, enclosing said memberwithin a filter medium, and sealing adjacent free edges of said filter medium together with a pliable adhesive insoluble in the solution being filtered to form an integra union.

6. A lter element, comprising a rigid drainage member surrounded by a filter medium, the

adjacent free edges of said filter medium being sealed together with a pliable adhesive agentV insoluble in the solution being filtered to form a tight union.

HERBER'I L. DICK. 

